This proposal represents the combination of two previously funded research centers into a single center oriented toward evaluation and modification of the research of physiologic systems to mechanical and thermal injury. It consists of a Core which supplies administrative and laboratory support, as well as a clinical research area with patient access and a reliable patient data base for 9 interrelated projects. The response to injury in defense against infection is investigated by projects involving immune response in thermal injury and smoke inhalaton and small vessel response to injury. The homeostatic system is evaluated by projects oriented toward understanding membrane transport in septic shock, interstitial changes in hypovolemic shock, and red cell oxygen transport in septic shock patients. Investigations of the pulmonary system include exploration of the pathophysiology of ARDS using the six inert gas techniques, indepth study of smoke inhalation injury in the animal model, and evaluation of the changes in pulmonary function induced by injury and treatment in patients. Evaluation of treatment modalities includes the development of photocoagulation scalpel, the effects of massive transfusion on physiologic function, and the development of a non-invasive index for cardiac performance.